All the interior angles of the polygon form A.P. The common difference is 6 degree..the greatest angle is 135 degree..find the number of sides of polygon.
I try to solve by using n/2[2a+(n-1)d]=(n-2)x180 but I can't solve it. I don't know what is the usage for giving me the greatest angle
We can thinking these angles to be an AP with the first term as $135,$ common difference $=-6$
So, the sum will be $\displaystyle\frac n2[2\cdot135+(n-1)(-6)]^\circ=n(138-3n)^\circ$
Now the sum of angles of $n$ sided polygon is $180(n-2)^\circ$